Related papers: An X-ray study for white dwarf binary AR Scorpii

Gamma-ray loud X-ray binaries are binary systems that show non-thermal broadband emission from radio to gamma rays. If the system comprises a massive star and a young non-accreting pulsar, their winds will collide producing broadband…

To understand physical processes such as mass transfer and binary evolution in X-ray binaries, the orbital parameters of the system are fundamental and crucial information. Cygnus X-3 is a high-mass X-ray binary composed of a compact object…

We report on XMM-Newton observations of the Black Widow pulsar, PSR B1957+20. The pulsar's X-ray emission is non-thermal and best modeled with a single powerlaw spectrum of photon index 2.03^{+0.51}_{-0.36}. No coherent X-ray pulsations at…

We present our second paper describing multi-wave-band, time-resolved spectroscopy of WZ Sge. We analyze the evolution of both optical and IR emission lines throughout the orbital period and find evidence, in the Balmer lines, for an…

We review the timing and spectral evolution of black hole X-ray binary systems, with emphasis on the current accretion-ejection paradigm. When in outburst, stellar mass black hole binaries may become the brightest X-ray sources in the sky.…

We report on a NIR, optical and X-ray campaign performed in 2017 with the XMM-Newton and Swift satellites and the VLT/HAWK-I instrument on the transitional MSP PSR J1023+0038. NIR observations were performed in fast-photometric mode in…

Recurring outbursts associated with matter flowing onto compact stellar remnants (black-holes, neutron stars, white dwarfs) in close binary systems, provide strong test beds for constraining the poorly understood accretion process. The…

X-ray irradiation in X-ray binaries is thought to control the behavior at the outer disc, which is observable mainly at optical wavelengths. It is generally parameterized phenomenologically, but it can also be predicted from theoretical…

Black widow and redback systems are compact binaries in which a millisecond pulsar heats and may even ablate its low-mass companion by its intense wind of relativistic particles and radiation. In such systems, an intrabinary shock can form…

There is solid observational evidence on the existence of massive, $M\sim 1~M_\odot$, highly magnetized white dwarfs (WDs) with surface magnetic fields up to $B\sim 10^9$ G. We show that, if in addition to these features, the star is fast…

Taking advantage of the very precise de Jager et al. optical white dwarf orbit and spin ephemerides; ASCA, XMMN, and Chandra X-ray observations spread over 10 yrs; and a cumulative 27 yr baseline, we have found that in recent years the…

The accreting millisecond X-ray pulsar (AMXP) SAX J1808.4-3658, shows a peculiar orbital evolution that proceeds at a much faster pace than predicted by conservative binary evolution models. It is important to identify the underlying…

Novae have been reported as transients for more than two thousand years. Their bright optical outbursts are the result of explosive nuclear burning of gas accreted from a binary companion onto a white dwarf. Novae containing a white dwarf…

Pulsed X-ray emission in the luminous, helium-rich sdO BD+37 442 has recently been discovered (La Palombara et al., 2012). It was suggested that the sdO star has a neutron star or white dwarf companion with a spin period of 19.2 s. After HD…

We report X-ray observations of the newly discovered pulsating white dwarf eRASSU J191213.9-441044 with Spectrum Roentgen Gamma and eROSITA (SRG/eROSITA) and XMM-Newton. The new source was discovered during the first eROSITA all-sky survey…

We report on the phase-coherent timing analysis of the accreting millisecond X-ray pulsar IGR J17591-2342, using Neutron Star Interior Composition Explorer (NICER) data taken during the outburst of the source between 2018 August 15 and 2018…

We report on the results from Suzaku broadband X-ray observations of the galactic binary source LS5039. The Suzaku data, which have continuous coverage of more than one orbital period, show strong modulation of the X-ray emission at the…

Neutron stars in X-ray binary systems are fascinating objects that display a wide range of timing and spectral phenomena in the X-rays. Not only parameters of the neutron stars, like magnetic field strength and spin period evolve in their…

We develop a model of the white dwarf (WD) - red dwarf (RD) binaries AR Sco and AE Aqr as systems in a transient propeller stage of highly asynchronous intermediate polars. The WDs are relatively weakly magnetized with magnetic field of…

There exists a special class of X-ray pulsars that exhibit very slow pulsation of $P_{\rm spin}>1000$ s in the high mass X-ray binaries (HMXBs). We have studied the temporal and spectral properties of these superslow pulsation neutron star…